Publication

Abstract : Neodymium doped alumino lead borate (LABNd) glasses were synthesized by the melt–quench method and systematically investigated to correlate structural evolution with optical performance. In the LABNd glasses, increasing Nd₂O₃ content leads to higher density and reduced molar volume due to enhanced BO₄ formation and network compactness. There is an increase in optical band gap energy (1.28–2.18 eV) and a decrease in refractive index (3.14–2.66). XRD and pair distribution function analysis confirm the amorphous nature with short-range order. The Raman spectroscopy reveals Nd–O vibrations (270–281 cm⁻¹) and significant high-frequency shifts (1458–1550 cm⁻¹), indicating transformation of metaborate units towards more polymerized diborate structures. UV–Vis absorption spectra show characteristic Nd³ ⁺ absorption bands (11,500–25,000 cm⁻¹), with the hypersensitive transition red-shifting from 581.5 to 582.5 nm, reflecting increased Nd–O covalency. Judd–Ofelt analysis yields a spectroscopic quality factor χ > 1 for Nd₂O₃ > 0.5 mol% and increasing thereafter, with high absorption cross-sections at 582 and 802 nm, identifying LABNd glasses as promising laser hosts. XPS results indicate increased network covalency and polymerization, evidenced by O 1 s shift (531.8–532.7 eV) towards higher binding energy, increased Al–O covalency and changes in Pb coordination collectively demonstrating composition-tuneable structural and optical properties suitable for laser applications.